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The miraculous light bulb

10 minutes

All you need to power an energy-efficient light bulb is a balloon and your hair! But it will only work in a dark room, like a toilet with no windows, or a closet.

Requirements

Steps

Step 1

Take the energy-efficient light bulb and the balloon, and go into the room, which should be completely dark. Inflate the balloon and tie it off with a knot. Keep the energy-efficient light bulb within reach.

Step 2

Turn off the light and rub the balloon on your hair, going back and forth about twenty times. You can also rub it on a woolly jumper.

Step 3

Then immediately hold the balloon against the glass of the energy-efficient light bulb. What happens next? Please note! Make sure the balloon doesn’t touch anything else before you hold it against the light bulb, or it will lose its static charge.

Tip
Hold the lamp against the balloon while rubbing it on your jumper.

Step

What did you discover

You can use a balloon to power an energy-efficient light bulb! An electric current is actually a charge in motion. Everything you see around you is made up of small particles with either a positive or a negative charge. If an object has a positive charge that is equal to its negative charge, it is neutral. By rubbing the balloon on your jumper, you separate the positive charge from the negative one, and the balloon becomes statically charged.

An energy-efficient light bulb contains gas. If this gas becomes negatively charged, it will light up. By holding the balloon against the light bulb, the negative charge inside the balloon flows into the light bulb. This is called electric discharge.